Taps are known in the art for delivering liquids, in particular of the type used for vessels called “bag in box.” Such vessels are composed of two external boxes, usually made of cardboard, inside which there is a bag containing the liquid to be delivered, to which bag usually a mouth, which is used for anchoring and constraining the delivering tap, is thermally welded.
An example of such prior art tap 50 is shown in FIG. 8 and is marketed by Conro Precision in Cape Town, South Africa. The tap 50 is applied to the bag with liquid, by inserting the body inside it through the above-described mouth and, upon using it by the end user, it is made to go out of the cardboard box through a hole, opened by operating on a pre-dinked part for such purpose. Then the tap 50 itself is actuated, by rotating the plug 52 with which it is equipped around a cam end 56.
These taps 50, though being simple from the constructive point of view, however have two types of deficiencies:
1) they are not equipped with warranty elements or seals, which signal tampering or unauthorized access attempts; and
2) the plug 52 with which they are composed is made of two parts (52, 54), thereby increasing the number of pieces and the end product cost, which instead, due to its manufacturing simplicity, should be kept as low as possible. Plugs are marketed in which the part 54 is not placed on the part 52, but such plugs have aesthetic problems, since in this way the injection spot of the part 52 remains visible from the outside.